Yarnold set a track record in her opener in Winterberg and improved her own mark in the fourth and final run today in 57.42 seconds to secure victory with an overall time of 3:49.95 minutes and continue Britain’s success in this event last won by Shelley Rudman.

Yarnold had never previously won the World Championships, with her best result coming in 2012 when she won a bronze medal at Lake Placid, and she had set winning this event as her main goal for the season, which she achieved in magnificent style.

Canada’s Elisabeth Vathje and Jacqueline Loelling, on her home track in Winterberg, took bronze and silver respectively, performing superbly at their first World Championships races, both at just 20 years of age.

But there was also plenty more for Great Britain to celebrate as Laura Deas and Rose McGrandle made it three Brits in the top ten as they finished seventh and ninth respectively.

Emanuel dug deep in the final of the 3000m to hold off the challenge of Norwegian Henrik Ingebrigsten and finish in a time of 7:45.54 minutes, but could do nothing to keep up with winner Ali Kaya of Turkey who clocked a new championship record of 7:38.42.

The 30-year-old rounded off a solid day for the Brits in the Czech Republic which started with success in the 60m heats for Dina Asher-Smith and Rachel Johncock.

That was followed promptly by Richard Kilty and Chijindu Ujah who will both have their sights set on progress to Sunday's final and top-spot on the podium.

There was relief for Jenny Meadows in the 800m after she finished fourth and was knocked out before being reinstated for Sunday's final after the disqualification of Russia's Anastasiya Bazdyreva.

Guy Learmonth will also go for gold in tomorrow's 800m final and there was a bronze medal in the 400m for Bundy-Davies.

European silver medalist. So honoured to be able to say that. Hardest race of my life today ran for the win but delighted with 2nd

America fight back on day two of Davis Cup clash

On day one Andy Murray and James Ward both won to hand hosts Great Britain a 2-0 lead, giving Jamie Murray and Dom Inglot the chance to claim an early victory.

Standing in their way though were veteran brother pairing Bob and Mike Bryan, and the Americans raced into an early two-set lead.

However Jamie Murray and Inglot dug deep and levelled the game, before succumbing to their visitors 9-7 in the fifth and final set.

All is not lost though with one final day to come, with Jamie Murray full of confidence that brother Andy can do the business against Isner in Glasgow, with the American having played for almost five hours against Ward.

“I’m sure he’ll [Andy] be pretty confident. I don’t know if Isner is going to be exactly back-flipping out of bed tomorrow morning to play Andy,” he said.

“I’d rather be in his shoes than Isner’s but I guess with his serve you’ve always got a chance but I’d never back against Andy in this situation.

“He has 7,000 Scottish, British people cheering him. He will want to go out and put on a good performance and beat Isner. I think we’re all fully confident that he will do that.”